Fitbits have become very common nowadays. Even you might be having one with you. But do you know how it works?
Everytime you check your heart rate,steps,calories,etc have you ever wondered how it comes up with those data?
So keep reading and let’s uncover the secret behind fitbits.
How fitbits Count steps?
Fitbits use a 3-axis accelerometer to determine the number of steps . Accelerometer converts movements into digital measurements.These measurements are then put into an algorithm that determines the number of steps you have covered.Basically a threshold distance is set.if the movement measures above the threshold then it is counted as a step.
We will have a separate blog on what accelerometers are exactly and how they work later on.
How does it determine the distance covered?
Distance covered is basically equal to the number of steps multiplied by your stride length. An average stride length is already set in the device depending upon your age and sex.Steps are counted using the step counting algorithm.Since we have both the data distance can be easily calculated using the above mentioned formula.
When you keep your GPS on , then the distance is calculated using GPS itself else it is done by the formula mentioned earlier.
How does it measure heart rate ?
Fitbits use a sensor called PPG to measure the heart beats.
It’s essentially testing how much red or green light it can see when looking at the skin on your wrist. Blood is red because it reflects red light and absorbs green light, so when your heart beats, there’s more blood flow in your wrist, and more green light absorption. Between heart beats, there’s less absorption of green light.
Now even though fitbits have become so popular , it doesn’t give accurate readings.Also these features except heart rate monitoring are incorporated in your smartphones as well.But still people find it cool and continues using it.